Multihead printing is still in the early days. The software isn't there: For example, RRF (Duet) would throw error messages for missing CAN boards when you would try pogo pins and only electrically connect the active tool head. The most advanced we have at the moment are toolchangers with 4-5 fixed tool-heads.
RRF/Duet in standalone is very stable and what you want. The flipside is that even through it is flexible with macros there are limits. This is more and more an issue that limits what can be done. Due to stability, I so far reject the idea of switching to Klipper (even duet in SBC mode isn't stable enough for my taste).
Also keeping track of heads is ugly at the moment. In a perfect world each toolhead would have an EEPROM and the machine would recognise it. Maybe even look up on a server/database what offset and parameter this tool needs so it could be swapped between tool-bays/docks and machines. For example with CNC milling it is state of the art that tool holder have RFID chips for tool identification and data is synced across the production floor (e.g. the shrink/tool setup station provides the tool data to a server and the CNC-mill controller gets the data automatically from this server).
As long as the basic connections are an open design.
If you like to install the same thing I can send you the Gerber, BOM and 3D-files for E3D toolchanger. In a nutshell this does nothing more than beeing "inserted" into the wire. If you want to call it special: platform agnostic. The small black header on the side is the auxiliary connector and is there for toolheads that require 5, 12 or 36V. For good measure three fuses (24V, 36V supply and heater).
Lets face it long term to gain the full ability of 3D printing. It will need to move to a multi material design.
end effector 1: FDM
end effector 2: FDM
end effector 3: silicon (paste/liquid)
end effector 4: subtractive milling *
- Head 4 will be soon upgraded to a rack system that allows to store upto 4 different heads so you can use 4 different subtractive tools (e.g. endmill, ball end mill, dove tail, thread cutter). An alternative to 4 subtractive heads could be 3 subtractive and 1 pick and place (those small vacuum pump are light enough to be mounted on a E3D toolchanger toolhead).
Sad part is that this type of setup will be for the next two decades exclusive to the DIY community or a company with deep pockets and good lawyers due to a removed Stratasys patent on making an electrical connection between toolhead and the gantry/mount.
The part that makes angry is this isn't even a Stratasys invention at all. Since the beginning of industrial robots, there have been electrical, pneumatic and liquid interfaces between the motion system and tool head. A toolchanging 3D-printer is a motion system with a tool head (e.g. filament extrusion) but this is locked behind a patent for this application.
